1. Field of the Invention
The present invention relates generally to an apparatus and method for supporting an Assisted Global Positioning System (AGPS) during an emergency service, and more particularly, to an apparatus and method for supporting an AGPS during the emergency service in a dual mode Mobile Station (MS).
2. Description of the Related Art
Natural disasters such as forest fires, typhoons, floods, etc., have given an increased importance to wireless emergency services. The wireless emergency service assists in emergency rescue of a person in an emergency circumstance and provides an emergency alert for a specific disastrous area. The wireless emergency service can be divided into a wireless emergency rescue service and a wireless emergency alert service. The wireless emergency rescue service is a service that detects a location of a wireless mobile communication user in an emergency and supports safe rescue of the user. The wireless emergency alert service is a service that supports delivery of emergency alerts, such as typhoon alerts, impending earthquake and tidal wave warnings, etc., to wireless subscribers within a specific geographical area.
The Federal Communications Commission (FCC) has defined Enhanced E911 (E911) regulations for providing a location of an MS through a network based method or an MS based method when there is an emergency call from the MS. In order to implement this, the 3rd Generation Partnership Project 2 (3GPP2) has introduced an AGPS corresponding to the MS based method, but current broadband wireless communication system (e.g., the Institute of Electrical and Electronics Engineers (IEEE) 802.16) fail to define AGPS standards. A broadband wireless communication service provider is in need of an AGPS function for the purpose of a Location Based Service (LBS), including E911 emergency service. In particular, the service provider has considered a scheme for supporting an AGPS function during E911 emergency service in a dual mode MS that supports a broadband wireless communication system and a Code Division Multiple Access (CDMA) system.
As described above, a current broadband wireless communication system has no definition of the AGPS standards for E911. Also, a broadband wireless communication system MS manufacturer seeks to realize an AGPS function in a broadband communication modulator/demodulator (modem) but suffers a difficulty due to, for example, patent royalty problems. In the case of CDMA, the 3GPP2 provides the AGPS standards for E911 and, generally, a CDMA modem already includes an AGPS function. Accordingly, when there is a request for E911 emergency service in a dual mode MS supporting a broadband wireless communication system/CDMA system, it can operate an AGPS through the CDMA modem and provide a location of an MS.
In general, when a modem supporting one communication mode is in operation, a dual mode MS inactivates a modem supporting a different communication mode to reduce power consumption. For example, a dual mode MS supporting a broadband wireless communication system and a CDMA communication system inactivates and disables a communication mode supporting a CDMA communication system, at a time a communication mode for accessing a broadband wireless communication system is in operation. Inversely, when a CDMA communication modem is in operation, a broadband communication modem does not operate.
Thus, an AGPS can operate during E911 emergency service only when a CDMA communication mode is in operation, but it is impossible to perform AGPS during E911 emergency service in a state where a CDMA modem is inactivated and only a broadband communication modem is in operation.